Autodesk 12812-051462-9011 User Guide 3 - Page 1044

Enable Final Gather When on, the mental ray renderer uses final gathering on page 7978 to create global illumination or to improve its quality. Default=on. This setting is also available on the Rendered Frame Window, as Final Gather on page 6081. TIP Without final gathering, global illumination can appear to be patchy. But final gathering increases rendering time. Leave Final Gather off to preview the scene, and then turn it on for the finished rendering. (Increasing the number of photons used to calculate global illumination can also improve global illumination.) Multiplier / color swatch Use these to control the intensity and color of the indirect light accumulated by final gathering. The defaults, 1.0 and white, produce physically correct rendering. This is useful for adjusting the contribution of the final gather effect, thus improving the quality of an image. FG Precision Presets Provides a quick, easy solution for final gather. The default presets are: Draft, Low, Medium, High, Very High, and Custom (the default choice). Available only when Enable Final Gather is on. The presets affect the following settings: ■ Initial FG Point Density ■ Rays per FG Point ■ Interpolate Over Num. FG Points The preset settings are defined in the text file mentalray_fg_presets.ini, found in the \plugcfg folder in the program installation. You can modify the existing presets and add new ones by editing this file. This setting is also available on the Rendered Frame Window, as Final Gather Precision on page 6083. Initial FG Point Density A multiplier for the density of final gather points. Increasing this value increases the density (and thus the quantity) of final gather points in the image. The points will therefore be closer together and more numerous. This parameter is useful for solving geometry problems; for example, near edges or corners. Default=1.0. TIP When adjusting final render settings it's often helpful to visualize the final gather points; to do so, turn on Diagnostics on page 6324 and choose the Final Gather option. mental ray Renderer | 6299